Aerosol generating system with means for disabling consumable

ABSTRACT

An aerosol-generating system is provided, including a storage portion configured to store an aerosol-forming substrate; an aerosol-generating element configured to generate an aerosol from the aerosol-forming substrate; a control circuitry in communication with the storage portion or the aerosol-generating element; and disabling means for rendering the storage portion inoperable in the aerosol-generating system in response to a disable signal from the control circuitry. There is also provided a method in an aerosol-generating system, including sending a disable signal from the control circuitry to the disabling component following a determination that an amount of the aerosol-substrate in the storage portion is below a threshold level or following a determination of a malfunction in the system.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional application of and claims the benefitof priority under 35 U.S.C. § 120 for U.S. Ser. No. 16/030,469, filed onJul. 9, 2018, which is a divisional application of and claims thebenefit of priority under 35 U.S.C. § 120 for U.S. Ser. No. 13/996,707,filed on Aug. 8, 2013, which is a National Stage application ofPCT/EP2011/073793, filed on Dec. 22, 2011, and claims benefit ofpriority under 35 U.S.C. § 119 from EP 10 252 236.4, filed on Dec. 24,2010, the entire contents of each of which are incorporated herein byreference.

The present invention relates to an aerosol generating system. Inparticular, the present invention relates to an aerosol generatingsystem in which the aerosol-forming substrate is liquid and is containedin a liquid storage portion.

WO 2007/078273 discloses an electric smoking utensil. A liquid is storedin a container which communicates with a heater vaporiser, powered by abattery supply, via a series of small apertures. The heater is in theform of a spirally wound electric heater mounted on an electricallyinsulating support. In use, the heater is activated by the mouth of auser to switch on the battery power supply. Suction on a mouthpiece bythe user causes air to be drawn through holes in the container, over theheater vaporiser, into the mouthpiece and subsequently into the mouth ofa user.

The aerosol generating systems of the prior art, including the smokingsystem referred to above, do have a number of advantages, but there isstill opportunity for improvement in the design, particularly concerningthe handling of the liquid storage portion.

According to a first aspect of the invention, there is provided anaerosol generating system comprising:

a storage portion containing an aerosol-forming substrate;

an aerosol generating element for generating an aerosol from theaerosol-forming substrate;

control circuitry in communication with the storage portion or theaerosol generating element; and

disabling means for rendering the storage portion inoperable in theaerosol generating system in response to a disable signal from thecontrol circuitry.

Preferably, the disabling means is part of the storage portion.Preferably the aerosol generating system is an electrically operatedsystem. The aerosol generating element is preferably electricallyoperated. Preferably, the storage portion is separable from a main bodyof the aerosol generating system, and the control circuitry is arrangedin the main body of the aerosol generating system.

It is advantageous to be able to automatically disable the storageportion for several reasons. If the storage portion is empty or nearlyempty, or if there is a system malfunction, the system may not produceaerosol with the desired characteristics, for example, aerosol particlesize or chemical composition. In addition, if the liquid storage portionis empty or nearly empty, disabling the storage portion is a means toinform the user the aerosol-forming substrate needs to be replaced.Also, automatically disabling the storage portion may be used toprevent, or at least make more difficult, the reuse of the storageportion refilled with inferior, inappropriate or even harmful substratematerials.

The aerosol generating system preferably further comprises a main bodyand the storage portion forms or is part of a consumable cartridgeconfigured to couple to the main body. It is advantageous to be able todisable a consumable cartridge but to maintain a main body as a reusablepart. The main body may include the more expensive components such ascontrol circuitry and a user interface.

Preferably, the disabling means is an electrical component that isconfigured to be switched or damaged by the disable signal. Preferably,the component is an electrical fuse that can be blown by a sufficientlyhigh current signal. Preferably the disable signal is a currentsufficient to blow the fuse. However, other electrical components may beused such as a switch or transistor. However, other means for disablingthe storage portion may be used. For example, the control circuitry maybe configured to optically check the storage portion before the aerosolgenerating element can be activated and the disabling means may be anelectrochromic material, or a thermochromic ink on the storage portionthat is heated by a heater in response to a disable signal.

Alternatively, in cases where the storage portion is recognized oridentified using logic circuitry (e.g. electric, electromagnetic oroptic) by means of a unique identifier, the same circuitry can be usedto write an ‘invalidate bit’ (flag bit) into the memory of thatcircuitry by which the storage portion is “disabled” and thus can not beused with the underlying aerosol generating system. However, in caseswhere the storage portion comprises such logic circuitry, the invalidatebit can even be stored on the storage portion itself, thus preventingits further use with another aerosol generating system.

The control circuitry is preferably configured to determine or estimatewhen an amount of aerosol-forming substrate in the storage portion isbelow a threshold amount, and to issue the disable signal when theamount of aerosol-forming substrate in the storage portion is determinedor estimated to be below the threshold amount. The control circuitry maydetermine the amount of substrate in the storage portion by directmeasurement, indirect measurement or by calculation. For example, thesystem may include means to directly measure the mass of the storageportion, such as balance. The control circuitry may be configured tocalculate the mass of substrate consumed by monitoring the use of thesystem. For example, the control circuitry may calculate substrateconsumption based on a number of times the aerosol generating elementhas been activated. Alternatively, the control circuitry may use achange in the behaviour of the system indicative of the storage portionbecoming empty to estimate the amount of substrate remaining in thestorage portion.

The threshold amount of liquid aerosol-forming substrate in the liquidstorage portion may be an absolute amount or a relative amount, e.g. apercentage value.

If the amount of liquid aerosol-forming substrate has decreased, forexample if the liquid storage portion is empty or nearly empty,insufficient liquid aerosol-forming substrate may be supplied to theaerosol generating element. In the case of a heater being used as theaerosol generating element, this may result in the temperature of theheater increasing. Thus, the temperature of the heater, as sensed by thetemperature sensor may allow the electric circuitry to determine thatthe amount of liquid aerosol-forming substrate in the liquid storageportion has decreased to a predetermined threshold.

The control circuitry is preferably configured to issue the disablesignal when the control circuitry has detected a malfunction in thesystem. For example, if a heater is used to generate aerosol, atemperature sensor may be used to detect any overheating of the heateror substrate. The temperature sensor is coupled to the control circuitryand the control circuitry issues a disable signal if the temperaturesensed by the temperature sensor exceeds a first temperature threshold.This is advantageous as it allows the system to prevent the generationof undesirable or harmful aerosol constituents.

The aerosol-forming substrate preferably has physical properties, forexample a boiling point, suitable for use in the aerosol generatingsystem. The aerosol-forming substrate is preferably a liquid. The liquidpreferably comprises a tobacco-containing material comprising volatiletobacco flavour compounds which are released from the liquid uponheating. Alternatively, or in addition, the liquid may comprise anon-tobacco material. The liquid may include water, solvents, ethanol,plant extracts and natural or artificial flavours. Preferably, theliquid further comprises an aerosol former. Examples of suitable aerosolformers are glycerine and propylene glycol.

Preferably the storage portion is configured such that the substrate inthe storage portion is protected from ambient air and, in someembodiments light, so that the risk of degradation of the substrate issignificantly reduced. Moreover, a high level of hygiene can bemaintained.

The aerosol generating element is preferably a heater configured to heatthe substrate. However, other aerosol generating elements can be used,such as a vibrating transducer.

The heater is preferably an electric heater. The electric heater maycomprise a single electric heating element. Alternatively, the electricheater may comprise more than one heating element, for example two, orthree, or four, or five, or six or more heating elements. The heatingelement or heating elements may be arranged appropriately so as to mosteffectively heat the liquid aerosol-forming substrate.

Preferably, the control circuitry is configured to issue a disablesignal in response to a temperature or resistance measurement. Morepreferably, the control circuitry is configured to issue a disablesignal in response to a determination that the temperature or resistanceof a heating element has exceeded a predetermined threshold.

The electric heating element (or elements) preferably comprises anelectrically resistive material. Suitable electrically resistivematerials include but are not limited to: semiconductors such as dopedceramics, electrically “conductive” ceramics (such as, for example,molybdenum disilicide), carbon, graphite, metals, metal alloys andcomposite materials made of a ceramic material and a metallic material.Such composite materials may comprise doped or undoped ceramics.Examples of suitable doped ceramics include doped silicon carbides.Examples of suitable metals include titanium, zirconium, tantalum andmetals from the platinum group. Examples of suitable metal alloysinclude stainless steel, Constantan, nickel-, cobalt-, chromium-,aluminium-titanium-zirconium-, hafnium-, niobium-, molybdenum-,tantalum-, tungsten-, tin-, gallium-, manganese- and iron-containingalloys, and super-alloys based on nickel, iron, cobalt, stainless steel,Timetal®, iron-aluminium based alloys and iron-manganese-aluminium basedalloys. Timetal® is a registered trade mark of Titanium MetalsCorporation. In composite materials, the electrically resistive materialmay optionally be embedded in, encapsulated or coated with an insulatingmaterial or vice-versa, depending on the kinetics of energy transfer andthe external physicochemical properties required. The heating elementmay comprise a metallic etched foil insulated between two layers of aninert material. In that case, the inert material may comprise Kapton®,all-polyimide or mica foil. Kapton® is a registered trade mark of E.I.du Pont de Nemours and Company.

The electric heating element may take any suitable form. For example,the at least one electric heating element may take the form of a heatingblade. Alternatively, the at least one electric heating element may takethe form of a casing or substrate having different electro-conductiveportions, or an electrically resistive metallic tube. The storageportion may incorporate a disposable heating element. Alternatively, oneor more heating needles or rods that run through the aerosol-formingsubstrate may also be suitable. Alternatively, the electric heatingelement may comprise a flexible sheet of material. Other alternativesinclude a heating wire or filament, for example a Ni—Cr, platinum,tungsten or alloy wire, or a heating plate. Optionally, the heatingelement may be deposited in or on a rigid carrier material.

The heating element may comprise a heat sink, or heat reservoircomprising a material capable of absorbing and storing heat andsubsequently releasing the heat over time to heat the aerosol-formingsubstrate. The heat sink may be formed of any suitable material, such asa suitable metal or ceramic material. Preferably, the material has ahigh heat capacity (sensible heat storage material), or is a materialcapable of absorbing and subsequently releasing heat via a reversibleprocess, such as a high temperature phase change. Suitable sensible heatstorage materials include silica gel, alumina, carbon, glass mat, glassfibre, minerals, a metal or alloy such as aluminium, silver or lead, anda cellulose material such as paper. Other suitable materials whichrelease heat via a reversible phase change include paraffin, sodiumacetate, naphthalene, wax, polyethylene oxide, a metal, metal salt, amixture of eutectic salts or an alloy.

The heat sink or heat reservoir may be arranged such that it is directlyin contact with the aerosol-forming substrate and can transfer thestored heat directly to the substrate. Alternatively, the heat stored inthe heat sink or heat reservoir may be transferred to theaerosol-forming substrate by means of a heat conductor, such as ametallic tube.

The heater may heat the liquid aerosol-forming substrate by means ofconduction. The heater may be at least partially in contact with thesubstrate. Alternatively, the heat from the heater may be conducted tothe substrate by means of a heat conductive element.

Alternatively, the heater may transfer heat to the incoming ambient airthat is drawn through the electrically operated aerosol generatingsystem during use, which in turn heats the aerosol-forming substrate byconvection. The ambient air may be heated before passing through theaerosol-forming substrate. Alternatively, the ambient air may be firstdrawn through the substrate and then heated.

Preferably, the aerosol forming substrate is a liquid at roomtemperature and the aerosol generating system further comprises acapillary wick for conveying the liquid aerosol-forming substrate fromthe storage portion to the aerosol generating element.

Preferably, the capillary wick is arranged to be in contact with liquidin the storage portion. Preferably, the capillary wick extends into thestorage portion. In that case, in use, liquid is transferred from thestorage portion to the electric heater (or other aerosol generatingelement) by capillary action in the capillary wick. In one embodiment,the capillary wick has a first end and a second end, the first endextending into the storage portion for contact with liquid therein andan electric heater being arranged to heat liquid in the second end. Whenthe heater is activated, the liquid at the second end of the capillarywick is vaporized by the at least one heating element of the heater toform the supersaturated vapour. The supersaturated vapour is mixed withand carried in the air flow. During the flow, the vapour condenses toform the aerosol and the aerosol is carried towards the mouth of a user.The liquid aerosol-forming substrate has physical properties, includingviscosity, which allow the liquid to be transported through thecapillary wick by capillary action.

The capillary wick may have a fibrous or spongy structure. The capillarywick preferably comprises a bundle of capillaries. For example, thecapillary wick may comprise a plurality of fibres or threads or otherfine bore tubes. The fibres or threads may be generally aligned in thelongitudinal direction of the aerosol generating system. Alternatively,the capillary wick may comprise sponge-like or foam-like material formedinto a rod shape. The rod shape may extend along the longitudinaldirection of the aerosol generating system. The structure of the wickforms a plurality of small bores or tubes, through which the liquid canbe transported by capillary action. The capillary wick may comprise anysuitable material or combination of materials. Examples of suitablematerials are capillary materials, for example a sponge or foammaterial, ceramic- or graphite-based materials in the form of fibres orsintered powders, foamed metal or plastics material, a fibrous material,for example made of spinned or extruded fibres, such as celluloseacetate, polyester, or bonded polyolefin, polyethylene, terylene orpolypropylene fibres, nylon fibres or ceramic. The capillary wick mayhave any suitable capillarity and porosity so as to be used withdifferent liquid physical properties. The liquid has physicalproperties, including but not limited to viscosity, surface tension,density, thermal conductivity, boiling point and vapour pressure, whichallow the liquid to be transported through the capillary device bycapillary action.

Preferably, the aerosol generating element is in the form of a heatingwire or filament encircling, and optionally supporting, the capillarywick. The capillary properties of the wick, combined with the propertiesof the liquid substrate, ensure that, during normal use when there isplenty of aerosol-forming substrate, the wick is always wet in theheating area.

The aerosol generating system may comprise a user display. In that case,the indication may comprise an indication on the user display.Alternatively, the indication may comprise an audible indication, or anyother suitable type of indication for a user.

The aerosol generating system may further comprise an electric powersupply. Preferably, the aerosol generating system comprises a housing.Preferably, the housing is elongate. If the aerosol generating includesa capillary wick, in use the longitudinal axis of the capillary wick andthe longitudinal axis of the housing may be substantially parallel. Thehousing may comprise a shell and a mouthpiece. In that case, all thecomponents may be contained in either the shell or the mouthpiece. In apreferred embodiment, the housing includes a removable consumablecartridge comprising the storage portion, the capillary wick and theheater. In that embodiment, those parts of the aerosol generating systemmay be removable from the housing as a single component.

The housing may comprise any suitable material or combination ofmaterials. Examples of suitable materials include metals, alloys,plastics or composite materials containing one or more of thosematerials, or thermoplastics that are suitable for food orpharmaceutical applications, for example polypropylene,polyetheretherketone (PEEK) and polyethylene. Preferably, the materialis light and non-brittle.

Preferably, the aerosol generating system is portable. The aerosolgenerating system may be a smoking system and may have a size comparableto a conventional cigar or cigarette. The smoking system may have atotal length between approximately 30 mm and approximately 100 mm. Thesmoking system may have an external diameter between approximately 5 mmand approximately 13 mm.

Preferably, the electrically operated aerosol generating system is anelectrically heated smoking system.

In a second aspect, the invention provides a cartridge for use in anaerosol generating system, the cartridge comprising

an aerosol forming substrate; and

disabling means for rendering the cartridge inoperable in the aerosolgenerating system, the disabling means configured to be activated by asignal from the aerosol generating system.

The aerosol forming substrate and disabling means may take any of theforms described in relation to the first aspect of the invention. Thecartridge may include a storage portion for storing the aerosol-formingsubstrate and may include a capillary wick as described in relation tothe first aspect of the invention. The cartridge may further include anaerosol generating element as described in relation to the first aspectof the invention. The cartridge may further include one or more ofcontrol circuitry, a power supply and a user interface as described inrelation to the first aspect of the invention.

In a third aspect, the invention provides an aerosol generating devicefor use with a consumable cartridge, the consumable cartridge containingan aerosol-forming substrate and a disabling means configured to renderthe cartridge inoperable in the aerosol generating device in response toa disable signal, the aerosol generating system comprising:

control circuitry configured to issue a disable signal to the disablingmeans when the amount of aerosol-forming substrate in the storageportion is determined or estimated to be below a threshold amount orwhen a malfunction is detected.

The control circuitry may be configured as described in relation to thefirst aspect of the invention. The aerosol generating device may furtherinclude an aerosol generating element as described in relation to thefirst aspect of the invention. The cartridge may further include one ormore of a power supply and a user interface as described in relation tothe first aspect of the invention.

According to a fourth aspect of the invention, there is provided amethod in an aerosol generating system comprising a storage portion forstoring aerosol-forming substrate, an aerosol generating element forgenerating an aerosol from the aerosol-forming substrate, controlcircuitry in communication with the storage portion and disabling meansassociated with the storage portion for rendering the storage portioninoperable in the aerosol generating system in response to a disablesignal from the control circuitry, the method comprising:

sending a disable signal from the control circuitry to the disablingmeans following a determination that an amount of the aerosol-substratein the storage portion is below a threshold level or following adetermination of a malfunction in the system.

According to a fifth aspect of the invention, there is provided electriccircuitry for an aerosol generating system, the electric circuitry beingarranged to perform the method of the second aspect of the invention.

According to a sixth aspect of the invention, there is provided acomputer program which, when run on programmable electric circuitry foran aerosol generating system, causes the programmable electric circuitryto perform the method of the second aspect of the invention.

Features described in relation to the aerosol generating system of theinvention may also be applicable to the method of the invention. And,features described in relation to the method of the invention may alsobe applicable to the aerosol generating system of the invention.

The invention will be further described, by way of example only, withreference to the accompanying drawings, of which:

FIG. 1 shows one example of an electrically operated aerosol generatingsystem having a liquid storage portion; and

FIG. 2 is a schematic illustration of a disabling mechanism suitable foruse in a system as shown in FIG. 1.

FIG. 1 shows one example of an electrically operated aerosol generatingsystem having a liquid storage portion. In FIG. 1, the system is asmoking system. The smoking system 100 of FIG. 1 comprises a housing 101having a mouthpiece end 103 and a body end 105. In the body end, thereis provided an electric power supply in the form of battery 107 andelectric control circuitry 109. A puff detection system 111 is alsoprovided in cooperation with the electric control circuitry 109. In themouthpiece end, there is provided a liquid storage portion in the formof cartridge 113 containing liquid 115, a capillary wick 117 and aheater 119. Note that the heater is only shown schematically in FIG. 1.In the exemplary embodiment shown in FIG. 1, one end of capillary wick117 extends into cartridge 113 and the other end of capillary wick 117is surrounded by the heater 119. The heater is connected to the electriccontrol circuitry via connections 121, which may pass along the outsideof cartridge 113 (not shown in FIG. 1). The housing 101 also includes anair inlet 123, an air outlet 125 at the mouthpiece end, and anaerosol-forming chamber 127.

In use, operation is as follows. Liquid 115 is conveyed by capillaryaction from the cartridge 113 from the end of the wick 117 which extendsinto the cartridge to the other end of the wick which is surrounded byheater 119. When a user draws on the aerosol generating system at theair outlet 125, ambient air is drawn through air inlet 123. In thearrangement shown in FIG. 1, the puff detection system 111 senses thepuff and activates the heater 119. The battery 107 supplies electricalenergy to the heater 119 to heat the end of the wick 117 surrounded bythe heater. The liquid in that end of the wick 117 is vaporized by theheater 119 to create a supersaturated vapour. At the same time, theliquid being vaporized is replaced by further liquid moving along thewick 117 by capillary action. (This is sometimes referred to as “pumpingaction”.) The supersaturated vapour created is mixed with and carried inthe air flow from the air inlet 123. In the aerosol-forming chamber 127,the vapour condenses to form an inhalable aerosol, which is carriedtowards the outlet 125 and into the mouth of the user.

In the embodiment shown in FIG. 1, the electric control circuitry 109and puff detection system 111 are preferably programmable. The electriccontrol circuitry 109 and puff detection system 111 can be used tomanage operation of the aerosol generating system. This assists withcontrol of the particle size in the aerosol.

FIG. 1 shows one example of an electrically operated aerosol generatingsystem according to the present invention. Many other examples arepossible, however. In addition, note that FIG. 1 is schematic in nature.In particular, the components shown are not to scale either individuallyor relative to one another. The aerosol generating system needs toinclude or receive an aerosol-forming substrate. The aerosol generatingsystem requires some sort of aerosol generating element, such as aheater or vibrating transducer, for generating aerosol from theaerosol-forming substrate. Finally, the aerosol generating systemrequires control circuitry for disabling the system. This will bedescribed below with reference to FIG. 2. For example, the system neednot be a smoking system. A puff detection system need not be provided.Instead, the system could operate by manual activation, for example theuser operating a switch when a puff is taken. For example, the overallshape and size of the housing could be altered. Moreover, the system maynot include a capillary wick.

However, in a preferred embodiment, the system does include a capillarywick for conveying liquid substrate from a storage portion to at leastone heating element. The capillary wick can be made from a variety ofporous or capillary materials and preferably has a known, pre-definedcapillarity. Examples include ceramic- or graphite-based materials inthe form of fibres or sintered powders. Wicks of different porositiescan be used to accommodate different liquid physical properties such asdensity, viscosity, surface tension and vapour pressure. The wick mustbe suitable so that the required amount of liquid can be delivered tothe heater. Preferably, the heater comprises at least one heating wireor filament extending around the capillary wick.

The aerosol generating system of the invention includes controlcircuitry that is operable to disable the cartridge 113. This may bedone for several reasons. In a preferred embodiment the controlcircuitry is configured for determining an amount of aerosol-formingsubstrate in the storage portion. When the liquid storage portion isdetermined to be empty or nearly empty, the control circuitry 109disables the cartridge 113. This is primarily because if the storageportion is nearly empty, insufficient liquid aerosol-forming substratemay be supplied to the heater. This may mean that the aerosol createdand inhaled by the user does not have the desired properties, forexample, aerosol particle size. This may result in a poor experience forthe user. In addition, it is advantageous to provide a mechanism wherebythe user can be informed that the liquid storage portion is empty ornearly empty. Then the user can prepare to replace storage portion.Disabling empty cartridges also provides for user safety. There is adanger that cartridges could be refilled with inferior and possiblydangerous substances. But by disabling the cartridges in a permanentmanner they cannot be refilled and reused.

FIG. 2 illustrates one embodiment of a disabling system that can beemployed in a system as described with reference to FIG. 1. Thedisabling system of FIG. 2 has two parts. One part is held in theconsumable cartridge 113 and the other part is held in the controlcircuitry 109. An electrical fuse 201 is located in the consumable. Aconnection port of three contacts 221 is used for interfacing theconsumable storage portion 113 and the main body of the device 101. Theconsumable part contains the heater element 119. The power supplied tothe heating element 119, which is in the form of a modulated signal, iscontrolled by the digital output 205 on the microcontroller 203 and viathe transistor T1. The positive battery electrode 207 is connected tothe other leg of the heating element 119 and the electrical fuse 201.

In the embodiment shown in FIG. 2 a determination that the cartridge 113is nearly empty is made by monitoring the temperature of the heatingelement 119. If the cartridge is nearly empty, insufficient liquidaerosol-forming substrate is supplied to the heater through the wick.This results in the temperature of the heater increasing, as less energyis used to vaporize vaporising the substrate. Thus, the temperature ofthe heater allows the control circuitry to determine that the amount ofliquid aerosol-forming substrate in the liquid storage portion hasdecreased to a predetermined threshold. Once the critical temperature isreached, the consumable is disabled to avoid a consumable violation bythe consumer like the refilling of the cartridge. Disabling alsoprovides the consumer with an indication that the consumable needs to bereplaced. Disabling the consumable also prevents the generation ofharmful constituents formed by an excess of heat.

The measurement of the temperature of the heating element is based onthe calculation of the current passing through the resistance 209. Thisis determined from the signal to input 213 and on the voltage of thebattery converted into digital values via two analogue inputs on themicrocontroller. As the temperature of the heating element increases, sodoes its resistance. The relationship between resistance and temperaturefor the heating element can be programmed or stored in themicrocontroller. When the microcontroller determines that the criticaltemperature has been reached, the microcontroller activates digitaloutput 211 connected to the transistor T2, which blows the electricalfuse 201. After this operation each time the user draws on the device,the microcontroller 203 checks the validity of the fuse 201 via aconsumable enable line 215 and if the connection is lost then the devicewill not operate. When the consumable is replaced by a new one, with anintact fuse, the system returns to normal operating mode.

It should be apparent that other means to disable the cartridge arepossible and other circuit configurations possible when using a fuse orother switchable or breakable electronic component. For example adedicated temperature sensor may be connected to the microcontrollerpositioned to detect the temperature of the heater element.

The control circuitry may be configured to advise the user when thecontrol circuitry has determined that the amount of liquid in the liquidstorage portion has decreased to a first threshold, and the cartridgedisabled when the control circuitry has determined that the amount ofliquid in the liquid storage portion has decreased to a secondthreshold. For example, if the aerosol generating system includes a userdisplay, it may be indicated on the user display that the liquid storageportion is empty or nearly empty and an estimate of the number ofremaining puffs before disabling will occur may be provided.Alternatively or additionally, an audible sound may indicate to the userthat the liquid storage portion is empty or nearly empty. Alternativemethods of indicating to the user that the liquid storage portion isempty or nearly empty are, of course, possible. An advantage of advisingthe user is that the user is then able to prepare to replace the liquidstorage portion.

The present invention provides a system and method for rendering aconsumable cartridge inoperable in an aerosol generating system. Thishas safety benefits as well as providing benefits in terms of userexperience and convenience. Although one particular embodiment has beendescribed, there are a number of ways of disabling the consumablecartridge and a number of conditions under which the disabling means maybe activated that fall within the scope of the invention.

1. An aerosol-generating system, comprising: a storage portionconfigured to store an aerosol-forming substrate: an aerosol-generatingelement configured to generate an aerosol from the aerosol-formingsubstrate; a control circuitry in communication with the storage portionor the aerosol-generating element; and disabling means for rendering thestorage portion inoperable in the aerosol-generating system in responseto a disable signal from the control circuitry, wherein the controlcircuitry is configured to determine or estimate when an amount ofaerosol-forming substrate in the storage portion is below a thresholdamount, and to issue the disable signal when the amount ofaerosol-forming substrate in the storage portion is determined orestimated to be below the threshold amount, and wherein theaerosol-generating system is an electrically operated smoking system. 2.The aerosol-generating system according to claim 1, further comprising amain body, wherein the storage portion is a consumable cartridgeconfigured to couple to the main body.
 3. The aerosol-generating systemaccording to claim 2, wherein the control circuitry is disposed in themain body of the aerosol-generating system.
 4. The aerosol-generatingsystem according to claim 1, wherein the disabling means is a componentthat is configured to be switched or damaged by the disable signal. 5.The aerosol-generating system according to claim 4, wherein thecomponent is an electrical fuse.
 6. The aerosol-generating systemaccording to claim 4, wherein the component is an electrical switch ordigital information interacting with the control circuitry andrepresenting an enable/disable state for the storage portion.
 7. Theaerosol-generating system according to claim 1, wherein the controlcircuitry is configured to issue the disable signal when the controlcircuitry has detected a malfunction in the aerosol-generating system.8. The aerosol-generating system according to claim 1, wherein theaerosol-generating element configured to generate the aerosol from theaerosol-forming substrate is a heater configured to heat theaerosol-forming substrate.
 9. A cartridge for an aerosol-generatingsystem, the cartridge comprising: an aerosol-forming substrate; anddisabling means for rendering the cartridge inoperable in theaerosol-generating system, the disabling means being configured to beactivated by a signal from the aerosol-generating system.
 10. Thecartridge according to claim 9, wherein the disabling means is anelectrical component that is configured to be switched or damaged by thesignal.
 11. An aerosol-generating device for a consumable cartridgecontaining an aerosol-forming substrate and a disabling means configuredto render the cartridge inoperable in the aerosol-generating device inresponse to a disable signal, the aerosol-generating system comprising:control circuitry configured to issue a disable signal to the disablingmeans when an amount of aerosol-forming substrate in the storage portionis determined or estimated to be below a threshold amount or when amalfunction is detected, wherein the aerosol-generating device is anelectrically operated smoking device.
 12. The aerosol-generating deviceaccording to claim 11, wherein the control circuitry is configured todetermine or estimate when an amount of aerosol-forming substrate in thestorage portion is below the threshold amount.
 13. A method in anelectrically operated smoking system comprising a storage portionconfigured to store an aerosol-forming substrate, an aerosol-generatingelement configured to generate an aerosol from the aerosol-formingsubstrate, control circuitry in communication with the storage portion,and disabling means associated with the storage portion configured torender the storage portion inoperable in the electrically operatedsmoking system in response to a disable signal from the controlcircuitry, the method comprising: sending a disable signal from thecontrol circuitry to the disabling means following a determination thatan amount of the aerosol-substrate in the storage portion is below athreshold level or following a determination of a malfunction in thesystem.